This invention relates to the assembly of seamed articles made from limp fabric. In particular, the invention relates to systems for automated, or computer-controlled, assembly of seamed articles from limp fabric.
Conventional assembly line manufacture of seamed articles constructed of limp fabric consists of a series of manually controlled assembly operations. Generally tactile presentation and control of the fabric-to-be-joined is made to the joining, or sewing, head under manual control. One drawback of this application technique is that the technique is labor intensive; that is, a large portion of the cost for manufacture is spent on labor. To reduce cost, automated or computer-cohtrolled manufacturing techniques have been proposed in the prior art. Such methods are exemplified by the U.S. patent applications incorporated herein by reference.
An automated approach to fabric presentation and control is disclosed in U.S. patent application Ser. No. 345,756. As there disclosed, pairs of belt assemblies are positioned on either side of a planar fabric locus. The respective belt assemblies are driven to selectively provide relative motion along a reference axis to layers of fabric lying in the fabric locus. A sewing head is adapted for motion adjacent to the fabric locus along an axis perpendicular to the reference axis. The respective belts maintain control of the limp fabric in the region traversed by the sewing head, with the respective belts being selectively retracted, permitting passage therebetween of the sewing head as it advances along its axis of motion. With this approach, control of the limp fabric is permitted in the regions which are to be joined. However, this control is maintained on a relatively coarse scale, and, further, the motions available to the fabric under such control are relatively limited.
Accordingly, it is an object of the present invention to provide an improved system for fabric presentation to a joining head.
It is another object to provide a system for joining layers of limp fabric while establishing two axis control of the respective layers of fabric. With such, axis control, easing (that is, joining of different length contours) may be attained, and as well as the formation of three dimensional seaming operations (wherein two same-length contours are joined).